Method of making platen rolls



July 11, 1944. J. Q. SHERMAN ET A1.

METHOD OF MAKING PLATEN ROLLS Original Filed Nov. 29, 1955 Patented July11, 1944 METHOD oF MAKING PLATEN ROLLS John Q. Sherman and Albert W.Metzner, Dayton, Ohio; said Metzner assignor to said Sherman; KatherineM. Sherman, William C. Sherman, and Wellmore B. Turner, executors saidJohn Q. Sherman, deceased Original application November 29, 1935, SerialNo. 52,169. Divided and this application October 22, 1938, Serial No.236,591

7 Claims.

This invention relates to platen rolls for writing machines and moreparticularly to the method of manufacture Of removably mounted rollswhich are interchangeable with other like platen rolls of differentlengths or of different surface characteristics, for use on typewriters,tabulating and computing machines and analogous mechanisms toaccommodate stationery of different widths or different surfacecharacteristics or materials.

The commercial production of such interchangeable platen rolls presentssome diilicult manufacturing problems, which are solved by theStructural features and method of manufacture forming the subject matterhereof.

While for illustrative purposes the present platen roll is shown inassociation with pin wheel feeding devices engageable in marginallypunched holes in the writing material, it is to be understood that itmay also be employed in association with other suitable mounting headsdevoid of feeding pins for use with frictional feeding means of awriting machine.

As herein shown and described, the present platen roll is longitudinallysplit to facilitate its installation and removal from between theaxially adjustable pin wheel units or mounting heads, thereby enabling asuccession of such platen rolls of different lengths or of differentsurface characteristics or degree of hardness to be employedinterchangeably with the same pin wheel units or mounting heads.

This application is a continuation in part of copending applicationSerial No, 687,303, filed August 29, 1933, now matured into LettersPatent No. 2,067,211, of January 12, 1937, and is a division ofcopending application Serial No. 52,169, now matured into Letters PatentNo. 2,173,864 containing article claims. Cross reference is made tocopending application Serial No. 68,219, filed March 11, 1936, nowmatured ii'ito Letters Patent No. 2,098,978.

The object of the invention is to improve the construction as well asthe mode of production of interchangeable platen rolls whereby they maynot only be economically manufactured but will be more efficient in use,of increased durability, greater -accuracy, and uniform character,easily interchanged and unlikely to get out of repair.

An important object of the invention is to provide an improved method ofsecuring the rubber or other surfacing material upon the core portionsof the platen roll sections to prevent accidental stripping or looseningwhile in use.

A further object of the invention is to provide an improved method ofproduction whereby uniformity of manufacture, accuracy of parts, andinterchangeability of sections is assured.

A further and important object of the invention is to facilitate thecommercial manufacture of sectional platen rolls herein described.

With the above primary and other incidental objects in view, as willmore fully appear in the specification, the invention consists of themethod or process and the steps thereof, and the mode of Operation, ortheir equivalents, as hereinafter described and set forth in the claims.

Referring to the accompanying `drawing wherein is shown the preferredbut obviously not necessarily the only form of embodiment of theinvention,

Fig. 1 is a side elevation of the platen roll assembly forming thesubject matter hereof.

Fig. 2 is a transverse sectional view on line 2-2 of Fig. 1.

Fig. 3 is a transverse sectional perspective view of one of the platenroll sections at a mid-length point.

Fig. 4 is a perspective end elevation of one of the platen rollsections.

Fig. 5 is an enlarged detail sectional view.

Like parts are indicated by similar characters of reference throughoutthe several views.

Referring to the drawing, i is the shaft of a platen rollto be mountedin suitable bearings in a writing machine carriage or in the frame of acomputing or tabulating machine, upon which are carried a pair of`axially adjustable mounting heads 2 and 3. For illustrative lpurposesthese mounting heads 2 and 3 in the present instance are shown as pinwheel units for feeding engagement with marginally punched holes inrecord material. It is to be understood, however, that the pin wheelfeed feature is not essential to the presentinvention and that thefeeding pins may be omitted from the mounting heads. The mounting heads2 and 3 are splined upon the shaft l for unison rotation therewith. Themounting head 2 is formed with an inwardly protecting hub 4 in which ismounted a radially disposed spline or key 5. The spline 5 is iixedlysecured in the hub l with its inner end projecting interiorly thereofinto engagement with a longitudinal keyway or groove in the shaft I tOafford positive rotative driving engagement therewith, and its outer endprojects beyond the periphery of the hub l into driving engagement witha slot intermediate the platen roll sections to afford a rotativedriving engagement between the roll sections and the mounting head. Theengagement of the inner end of the keyway or spline 5 within thelongitudinal slot 8 of the shaft I permits axial adjustment of themounting head 2 upon the shaft while maintaining lts driving engagementtherewith in all positions of such adjustment. In order to secure themounting head 2 in any one of several positions of axial adjustment, thehub 4 is provided with a transverse slot in which is pivotally mounted asegment-shaped key or latch 8 engageable in any one of a series ofnotches 9 in the periphery of the shaft I under influence of a spring Iseated in a bore in the hub 4.

By lifting the latch 8 against the tension of the spring I0 as shown bydotted lines in Fig. 2, the mounting head 2 is released from the shaftfor sliding adjustment thereon to different position, in which it isagain held by the engagement of the latch 8 in the corresponding notch9. The inner face of the mounting head 2 is provided with an angular orV-shaped rib II in concentric spaced relation with the hub 4 forengagement in corresponding grooves in the extremities of the platenroll sections to be described.

The opposite mounting head 3 is of the same general character; having acorresponding inwardly projecting hub 4 having a key or spline alsoengaging in thelongitudinal slot 6 of the shaft I to afford drivingengagement. The mounting head 3 is also provided with the concentricangular rib II for interlocking engagement with the platen roll sectionbut does not have the splined rotative driving connection therewith. Themounting head 3 is not locked in definite position upon the shaft I butis free for sliding movement thereon relative to the opposite mountinghead 2. It is held in its position of adjustment by a thrust collar ordisc I3 screw-threaded upon the extremity I0 of the shaft I and bearingagainst the outer side of the mounting head.

The ,platen roll comprises two longitudinally separablesenil-cylindrical sections I5, which are interposed between and engagedby the respective mounting heads 2 and 3. The platen roll sections I5comprise an inner core or rigid support I 6 which preferably, althoughnot necessarily, is initially a length of metal tubing severedlongitudinally and the severed edges reduced sufficiently to accommodatethe overlapping portions of the outer or cover stratum of rubber or thelike. The .platen roll is not divided exactly upon its diametricalplane. In order to offset the longitudinal joint of the platen rollrelative to the line spacing means and the feeding pins, and especiallyto avoid possible registry of the platen roll joints with the writinglines as the joints or lines of severance of the platen roll pass thewriting position, one platen roll section is slightly larger than theother. The standard line spacing of typewriters and such machines is sixlines to an inch and the standard size platens used in such machineshave a circumference of flve and onehalf inches. Thus, one revolution ofthe platen produces thirty-three equally spaced writing lines. If such aplaten were divided on a diametrical plane, to produce two sections ofequal size there would be sixteen and one-half writing lines in eachsection which places the platen roll joint coincident with a writingline. In order to overcome this objectionable feature, one of thesections is increased in size with a corresponding decrease in size ofthe companion section sufficient to prevent vthe spliting of a writingline by the platen roll joint. For illustrative purposes, but withoutintent of limiting the invention to any specific dimension, in practiceone section of a standard size of platen roll is 1%3 of itscircumferential dimension while the other section is 1%,3 thereof. Thusthere is provided seventeen complete writing lines in one section andsixteen writing lines in the companion section, the platen roll jointbeing dis posed intermediate the sixteenth and seventeenth writinglines. Being of such slightly different size, the two portions of theroll have the appearance of being equal size and halves of the cylinder,in which case the joint or line of severance of the sections wouldcoincide with writing lines as the platen roll is rotated. Not only isthe division of the cylindrical roll at variance with the diametricalplane, but the adjacent marginal faces I8 of the core portion I6 arepreferably beveled or inclined inwardly slightly in divergent relationwith their radial planes as is shown more clearly in the enlarged detailView, Fig. 5.

The opposite ends of the internal core or supporting members I6 areprovided with concentric angular grooves I9 which conform to andreceive. the concentric ribs II of the respective mounting heads 2 and 8when the platen roll is assembled therebetween. Likewise the adiacentmarginal faces of the respective core portions I6 are relieved or cutaway as at 20 in Fig. 3 to afford therebetween a slot to receive theouter end of the key or spline 5 when the platen roll sections I5 areassembled one upon the other.

Fixedly secured about the outer convex surfaces of the semi-cylindricalcores I6, preferably by being vulcanized thereto, are the cover strataI'I of rubber or the like, which cover strata are continued at theopposite edges of the core member I6 into overlapping relation with theinwardly beveled marginal surfaces Il thereof. In this manner theresilient cover portion I1 is clenched over the edge of the core andinterlocked therewith so that the danger of accidental loosening orstripping of the resilient surfacing material I'I from the core I8 isminimized. This is especially true when the complementary sections ofthe platen roll are engaged one with the other in abutting relation andso held between the mounting heads 2 and 3, in which case theoverlapping marginal extensions 2I of the resilient cover strata I1 areclamped between the respective core portions I5.

In the manufacture of the sectional platen roll elements I5 the outerfaces of the core portion IB are preferably, although not necessarily,etched, roughened. or otherwise treated to facilitate adhesion of theoverlying rubber surface strata II. The resilient cover II of rubber orthe like is then molded and vulcanized about the convex face of the coreportion I6 and in overlapping relation with the marginal faces I8thereof as at 2i. After being vulcanized, the overlapping marginalextensions 2I of the sections are accurately ground or otherwisefinished to afford uniform smooth surfaces coincident with 'the radialplane of the unit. As before mentioned, in order to offset the juncturelines out of registry with the writing lines as the platen rotates,these finished surfaces of the respective sections preferably do not liein a common plane but are slightly angular relative to each other.

After the contacting or abutting surfaces of the marginal extensions 2|have been reduced to a uniformly fiat smooth surface by grinding orotherwise, the complementary sections of the platen roll are assembledin contacting relation with each other and so held while the outercylindrical surfaces of the surfacing material I1 is reduced to a smoothfinished cylindrical surface throughout by grinding or otherwise. Bysuch method the` respective sections of' the roll are so accuratelyfitted and conformed one to the other that the juncture lines or jointsare hardly perceptible. These platen roll sections are manufactured indifferent lengths for use with record material of different width. Thesurface covering Il may also Abe of differentmaterials, or if of rubberthey may be of differentA degrees of hardness or of different surfacefinish to accommodate the platen rolls to different conditions of useand to use with materials of different character. Likewise, in lieu of arubber or other resilient surface covering I1, such surfacing materialmay be of a hard resistant character such as pyroxylin or Celluloid ormay be metal surfaced for stencil cutting purposesand the like.

It will be understood that by the present construction of platen rollssuch roll sections of different sizes, different character or differentsurfacing material may be interchangeably mounted between the adjustablemounting heads 2 and 3 as the occasion and character of work to beperformed may require.

In order to interchange one pair of platen rolls for another ofdifferent size or surface characteristics, the pressure collar or discI3 is relieved by unscrewing it upon the threaded extremity I2 of themain shaft I, thereby relieving the mounting head 3 for limitedretractive movement upon the shaft I. By such retractive movement of themounting head 3 its angular bead II is withdrawn from the terminalgroove I9 of the platen roll section 5, thereby releasing the sectionwhich may be readily moved out of interlocking engagement with theconcentric angular bead IIl of the opposite mounting head 2. In theevent that the platen roll to be substituted is of less length, themounting head 2 is axially adjusted upon the shaft I by disengaging thetransverse latch 3 from the notch 9 and shifting the head 2 vupon theshaft to a position corresponding to the length of the substitute rollsections, whereupon the mounting head 2 is again interlocked with theshaft by engagement of its latch member 8 in another of the series ofnotches 9 in the shaft. The substitute roll sections are then placed inposition about the shaft I with one grooved end thereof engaging withthe angular bead Il of the mounting head 2, while the opposite mountinghead y3 is shifted upon the shaft I into abutting relation with theopposite end of the platen roll section, within the concentric groove I9of which the angular bead II of the head 3 engages. The mounting head 3is thereupon held in such abutting or clamping relation with the platenroll sections by adjustment of the thrust collar or/disc I2 upon thescrew-threaded extrem-- ity I3 of the shaft.

In lieu of finishing the abutting surfaces of the portions 2l uponslightly angular radial planes as before mentioned, for economy andconvenience of manufacture the opposite margins 2I may be finished in acommon flat plane, which, due to the slight difference in the size ofthe sections, will be offset'slightly from the diametrical plane of theroll. This enables both margins of the respective sections to besimultaneously finished by passing them beneath a cylindrical grinder ortheflike having uniform operative engagement with both margins.

From the above description it will `be apparent that there is thusprovided a'device of the character described possessing the particularfeatures of advantage before enumerated as desirable but which obivouslyis susceptible of modification in its form, proportions, detailconstruction and arrangement of parts without departing from theprinciple involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown, but that the means and construction herein disclosedcomprise the preferred form of several modes of putting the inventioninto effect, and the invention is therefore claimed in any of its formsor modifications within the legitimate and valid scope of the appendedclaims.

Having thus described our invention, we claim:

1. The herein described method of producing platen rolls for writingmachines including providing a plurality of separable segments of acylinder molding a surface cover about the convex faces of the segmentsand over the longitudinal marginal edges thereof, reducing thelongitudinal marginal faces of the segments to plane surfaces, fitting aplurality of segments together with their plane marginal surfaces inabutting engagement into a composite circular body and reducing theexterior of the composite body to a uniform cylindrical body.

2. The herein described method of producing a platen roll for a writingmachine including providing a plurality of segments of a cylindertotaling somewhat less than a complete cylinder whereby the segmentswill be separated by interfvening spaces when equally spaced inassembled cylindrical relation, covering the convex faces of thesegments with a stratum of cover material, extending the cover materialinwardly about the longitudinal margins of the segments and assemblingthe covered segments into a cylindrical roll with the inwardly extendingmargins of cover material gripped between succeeding sections.

3. The herein described method of producing sectional platen rolls,including the steps of forming a plurality of concave-convexreinforcement members, reducing the marginal faces thereof to reentrantconformation, applying to the exterior convex faces thereof coverstrata, extendingl the cover strata over the reentrant marginal faces ofthe reinforcement members into interlocked engagement therewith, andassembling the segments into a cylindrical body with the marginalextensions of the cover strata in abutting relation between succeedingsegments.

4. The herein described method of producing platen rolls for writing andimprinting apparatus, including surface finishing the marginal edges ofeach of two longitudinally separable platen roll segments of differentcircumferential dimensions on angularly disposed radial planes thereofinto matching relation with the angularly disposed marginal edges of theother separable segment of the platen roll, assembling the matchingsegments with the finished radial faces of each of the segments incontact with the radial faces of the other segment, and finishing theexterior faces of the segments into concentric ycylindrical form.

5. The herein described method of producing platen rolls for writing andimprinting apparatus wherein record material is progressively advancedcoincident with step by step rotation of a platen roll having an unevennumber of circumferentially spaced writing positions thereon, includingsevering a length of metal tubing longitudinally into unequal halves ofcores and into lengths corresponding to the desired platen lengths,forming beveled edges along the longitudinal edges of thesemi-cylindrical cores, securing to the convex surfaces of the corescover strata of rubber with marginal extensions thereof overlapping theedges of the cores, vulcanizing the rubber cover strata, accuratelygrinding the marginal extensions thereof to coincide with radial planesof the semi-cylindrical unit, assembling two such units into a completecylinder, and lastly, grinding the exterior face of the assembly to asmooth finished true cylindrical surface.

6. The herein described method of producing platen rolls for writing andimprinting apparatus wherein record material is progressively advancedcoincident with rotation of a platen roll, including the step of surfacecovering longitudinally separable cylindrical segments of a platen rollwith a facing material, extending the margins of the facing materialabout the edges of the segments for clamping engagement between adjacentsegments, assembling the covered segments into grouped relation andsubsequently surface finishing the exterior faces of the coverings ofthe segments into concentric relation.

'7. The herein described method of producing platen rolls for writingand imprinting apparatus wherein record material is progressivelyadvanced coincident with rotation of a platen roll, including the stepsof providing longitudinally separable cylindrical segments of a roll,enclosing the respective segments in surface coverings having marginalflanges overlapping the margins of the segments and providing reentrantangles engaging the margins of the segments in interlocking relation inthe reentrant angles o! the surface covering, assembling the coveredsegments in circular grouped relation and subsequently reducing theexterior faces thereof to concentric flush relation.

JOHN Q. SHERMAN. ALBERT W. METZNER.

